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Full text of "The manufacture and properties of iron and steel"

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424                                    THE IRON INDUSTRY.
Europe, and the newest plants have not copied America, but have enlarged and expanded the old two-high construction.
In making structural material and railway splices, it is the custom in America to cut the ingot into several blooms or billets and reheat for finishing, this being done in order that the bloom or billet mill shall run at its maximum capacity. In Europe little thought is given to this argument. The question everywhere heard is this: "What could we do with all the steel if we should run continuously ?" It is therefore more common abroad to roll many different sections in one reversing mill, the stuff being'finished in one heat from the ingot, the finished bar being very long; in one mill a 2-in. square billet is finished 475 ft. long and a 3 in. x 3 in. angle 425 ft. Oftentimes the finishing is done on a different mill, and frequently the finishing mill is three-high, the blooms being cut up and transferred without reheating.
The Germans use many three-high trains for finishing, and 15-irich beams are rolled directly from the ingot without cropping the ends and without reheating,- the work being done by hooks and tongs without any machinery except a steam cylinder to raise the swinging support of the hooks used to catch the piece. Such a lifting motion is necessary when the rolls are 30 inches in diameter and the mill runs 110 to 120 revolutions. I have seen a mill of this size and speed handling 8-inch blooms weighing about 1200 pounds, and few American workmen would care to work as fast and as hard as these hookers, although American workmen would have smiled at the idea of a man being able to do anything when wearing wooden shoes. In rolling beams by hand in a train of that size an army of men is required, and the average visitor can hardly understand why some simple labor-saving devices are not introduced. It is Delated of an American at a German works that he offered to spend a certain reasonable sum in machinery and save so many dollars every month. The manager answered by showing him the cost sheets and proved that the total expenses for labor in the mill did not equal what he proposed to save. Such an answer cannot be true of all places where labor is thrown away. In one of the famous steel works of the world are two blooming mills, three-high, and exactly alike, turning out a combined product of ten thousand tons per month. In America one such mill would take care of from forty to sixty thousand tons per month and two men on each